From 510a661596ef3c8673c224750b80eb7c1f95cd7a Mon Sep 17 00:00:00 2001
From: Andrew Wilkins <axwalk@gmail.com>
Date: Sun, 2 Aug 2015 12:16:57 +0000
Subject: [PATCH] Add support to set/get ordering for load/store from the C API

Summary: As per title

Reviewers: chandlerc, bogner, majnemer, axw

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11141

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243847 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm-c/Core.h |  2 ++
 lib/IR/Core.cpp       | 35 ++++++++++++++++++++++++++++++++++-
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/include/llvm-c/Core.h b/include/llvm-c/Core.h
index 764dbfac342..ac0b10a6ff6 100644
--- a/include/llvm-c/Core.h
+++ b/include/llvm-c/Core.h
@@ -2792,6 +2792,8 @@ LLVMValueRef LLVMBuildGlobalStringPtr(LLVMBuilderRef B, const char *Str,
                                       const char *Name);
 LLVMBool LLVMGetVolatile(LLVMValueRef MemoryAccessInst);
 void LLVMSetVolatile(LLVMValueRef MemoryAccessInst, LLVMBool IsVolatile);
+LLVMAtomicOrdering LLVMGetOrdering(LLVMValueRef MemoryAccessInst);
+void LLVMSetOrdering(LLVMValueRef MemoryAccessInst, LLVMAtomicOrdering Ordering);
 
 /* Casts */
 LLVMValueRef LLVMBuildTrunc(LLVMBuilderRef, LLVMValueRef Val,
diff --git a/lib/IR/Core.cpp b/lib/IR/Core.cpp
index 0eb88a96757..a3768485fd5 100644
--- a/lib/IR/Core.cpp
+++ b/lib/IR/Core.cpp
@@ -2489,7 +2489,6 @@ LLVMValueRef LLVMBuildFree(LLVMBuilderRef B, LLVMValueRef PointerVal) {
      CallInst::CreateFree(unwrap(PointerVal), unwrap(B)->GetInsertBlock())));
 }
 
-
 LLVMValueRef LLVMBuildLoad(LLVMBuilderRef B, LLVMValueRef PointerVal,
                            const char *Name) {
   return wrap(unwrap(B)->CreateLoad(unwrap(PointerVal), Name));
@@ -2515,6 +2514,21 @@ static AtomicOrdering mapFromLLVMOrdering(LLVMAtomicOrdering Ordering) {
   llvm_unreachable("Invalid LLVMAtomicOrdering value!");
 }
 
+static LLVMAtomicOrdering mapToLLVMOrdering(AtomicOrdering Ordering) {
+  switch (Ordering) {
+    case NotAtomic: return LLVMAtomicOrderingNotAtomic;
+    case Unordered: return LLVMAtomicOrderingUnordered;
+    case Monotonic: return LLVMAtomicOrderingMonotonic;
+    case Acquire: return LLVMAtomicOrderingAcquire;
+    case Release: return LLVMAtomicOrderingRelease;
+    case AcquireRelease: return LLVMAtomicOrderingAcquireRelease;
+    case SequentiallyConsistent:
+      return LLVMAtomicOrderingSequentiallyConsistent;
+  }
+
+  llvm_unreachable("Invalid AtomicOrdering value!");
+}
+
 LLVMValueRef LLVMBuildFence(LLVMBuilderRef B, LLVMAtomicOrdering Ordering,
                             LLVMBool isSingleThread, const char *Name) {
   return wrap(
@@ -2567,6 +2581,25 @@ void LLVMSetVolatile(LLVMValueRef MemAccessInst, LLVMBool isVolatile) {
   return cast<StoreInst>(P)->setVolatile(isVolatile);
 }
 
+LLVMAtomicOrdering LLVMGetOrdering(LLVMValueRef MemAccessInst) {
+  Value *P = unwrap<Value>(MemAccessInst);
+  AtomicOrdering O;
+  if (LoadInst *LI = dyn_cast<LoadInst>(P))
+    O = LI->getOrdering();
+  else
+    O = cast<StoreInst>(P)->getOrdering();
+  return mapToLLVMOrdering(O);
+}
+
+void LLVMSetOrdering(LLVMValueRef MemAccessInst, LLVMAtomicOrdering Ordering) {
+  Value *P = unwrap<Value>(MemAccessInst);
+  AtomicOrdering O = mapFromLLVMOrdering(Ordering);
+
+  if (LoadInst *LI = dyn_cast<LoadInst>(P))
+    return LI->setOrdering(O);
+  return cast<StoreInst>(P)->setOrdering(O);
+}
+
 /*--.. Casts ...............................................................--*/
 
 LLVMValueRef LLVMBuildTrunc(LLVMBuilderRef B, LLVMValueRef Val,
-- 
2.34.1